U.S. Pat. No. 3,891,175 to Hawley et al teaches a traffic signal hanger which is adjustable about two axis for vertical hanging of the traffic signal housing and permits damped pivoting of the traffic signal housing about one horizontal axis.
The device of Hawley has elements of the hanger hingedly coupled together about one axle member with opposed helical metal springs biasing the elements to a neutral position. With the device having specific axle and journalling elements, a passageway for wire is spaced above the axle and journalling elements increasing the relative size of the device. The Hawley device suffers from the disadvantage of requiring specific axle and journalling elements and being limited in the extent to which it can be made compact yet maintain internal passageways for electrical wire.